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Volume 46, Issue 12
Displaying 1-18 of 18 articles from this issue
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Nobuyuki OHTA, Yasuo KOBAYASHI, Yasuhiro FURUKAWA1980 Volume 46 Issue 12 Pages 1453-1458
Published: December 05, 1980
Released on J-STAGE: June 30, 2009
JOURNAL FREE ACCESSThis report deals with the maximum limit tgmax of filling time tg in which molten metal is able to be enough filled into the cavity of dies. In order to make good die castings, the molten metal injected from the gate of dies must be completely filled in the cavity, before the beginning of the solidification of molten metal. The die castings of various wall thickness can be die-casted by the installation of the core of different outer size in the dies. The filling time tg is calculated by the equation tg=Qg/av, where a is the sectional area of gate, Qg the volume of cavity, and the velocity v of molten metal from gate is obtained by the speed meter of casting plunger. On the other hand, E. W. Rearwin investigated the solidification time τ of Al-alloy die castings in the dies according to their wall thickness. By the experiment, it is shown that the maximum limit tgmax of the filling time tg in which molten metal is able to be well filled in the dies is equal to the above solidification time τ.View full abstractDownload PDF (2888K) -
Tool Life and Selection of Operating Parameters in GrindingTsutomu SHIMAMUNE, Kohji ONO1980 Volume 46 Issue 12 Pages 1459-1466
Published: December 05, 1980
Released on J-STAGE: June 30, 2009
JOURNAL FREE ACCESSThe tool life in precision grinding process is discussed theoretically based on the variation in grinding forces with the progress of time. From the results, the effects of dressing conditions and grinding conditions on the tool life in grinding are clarified and verified experimentally. A summary of the results is shown below. (1) The percent wear flat area to the working area of grinding wheel at the beginning of burn is not fixed, and varies according to the effects of grinding conditions. (2) The type (grinding burn type or chatter mark type as a result of bond fracture) and the time of tool life in grinding can be estimated by the mutural relation between dressing and operating conditions. (3) When the ratio of work velocity to wheel velocity is small, the merits of high-speed grinding could not be expected to obtain. (4) In order to prevent the growth of grinding burn in case of larger depth of cut and lower work velocity, it is convenient to apply the lower wheel velocity.View full abstractDownload PDF (1697K) -
A Design Model with Two Dimensional PatternsToshio KOJIMA, Kimio TAMURA, Choichiro SODA, Fumio ASUKE, Seiji NAKAHA ...1980 Volume 46 Issue 12 Pages 1467-1473
Published: December 05, 1980
Released on J-STAGE: June 30, 2009
JOURNAL FREE ACCESSThe serial studies aim to establish a CAD system which can solve the specifications of the progressive blanking die required to produce a desired product, when the specifications of the product is given as input information. The present paper makes the mathematical model of this designing process clear. The results obtained are summarized as follows. (1) The geometry of the product is first represented by a set of two dimensional patterns, then the required die is designed in such a way as its shape being described by a set of columns which are obtained by sweeping the patterns along the die working direction. (2) In connection with the design parameters along the die operational direction and those on the planes vertical to the direction, the design process is classified separately into two parts. (3) The design parameters on the planes are decided by the three steps; the specifications of the point contour shapes of the tools, the blank layout and the tool layout. They are represented by the set operations of two dimensional patterns, respectively.View full abstractDownload PDF (1351K) -
Kenichi TANAKA, Hiroshi YANO1980 Volume 46 Issue 12 Pages 1474-1480
Published: December 05, 1980
Released on J-STAGE: June 30, 2009
JOURNAL FREE ACCESSIn the training of the measuring technique, the evaluation of both the training and its effect is one of the important questions to be asked. Especially, in the measurement using the microscope, it should not be overlooked that the error in measurement is, in many instances, attributable to the observer. In this paper, the discussion is concerned with the setting of the training goal, and the guideline for the evaluation of the training effect, and in this connection, the method for the evaluation of the training effect, and the difference in the training effect resulting from the difference of the training method are also discussed. As a result, it has been clarified that (1) in evaluating the training effect, the use of the SN ratio in the measurement is most reasonable and effective; (2) as for the training method, the uses of the manual for the measuring technique, presentation of the pattern in a state of the correct coincidence and the training to take the feedback of the result, especially the uses of the last two have high effect; (3) the greater the complexity of the object to be measured, the greater the effect of the training; (4) where it is aimed to increase the effect of training by the repetition of the training, the training method featuring the feedback of the result of measurement is recommendable.View full abstractDownload PDF (1359K) -
Shigeru UENO, Toshimichi MORIWAKI, Kazuaki IWATA1980 Volume 46 Issue 12 Pages 1481-1486
Published: December 05, 1980
Released on J-STAGE: June 30, 2009
JOURNAL FREE ACCESSDynamic behaviours of impact dampers are nonlinear, and hence sophisticated computations are required when applying them in practice. In the present study, the impact damper is applied to a boring bar in order to improve machining performances, and its dynamic performances and effects are evaluated employing the impulse response method. The responses of the boring bar equipped with an impact damper were simulated at first with use of a digital computer and the transfer functions were computed employing FFT algorithm. Two types of boring bars were manufactured, which are equipped with impact dampers with various masses and clearances. The dynamic characteristics of the boring bars were measured. employing the impulse response method, and stability limits against chatter vibrations were obtained by cutting tests. Good correlations were observed between the simulations and the measurements, and the measured dynamic compliances and the experimental stability limits. It is concluded that the present technique is useful to optimize the mass and the clearance of the impact damper.View full abstractDownload PDF (1038K) -
The Function in Constant Feed Cylindrical Plunge GrindingTakashi UEDA, Yoshiaki KODAMA, Akira YAMAMOTO1980 Volume 46 Issue 12 Pages 1487-1492
Published: December 05, 1980
Released on J-STAGE: June 30, 2009
JOURNAL FREE ACCESSThe purpose of this paper is to investigate the critical phenomenon in grinding operation with constant infeed, and to obtain the evaluating function capable to express satisfactorily and universally the severity of grinding conditions on cutting behavior. The experimental method used is cylindrical plunge grinding, where a carbon steel is ground by A-wheels of various grades in grain size and hardness. Even in case of constant feed similar to that of constant stone pressure machining, the critical phenomenon is observed, and feed rate and work surface speed influence on the grinding distance in which the phenomenon arises. The evaluating function ψ, namely, grinding condition term in the familiar equation representing theoretically the maximum cutting depth of an active grain, cannot fairly express the severity of grinding condition, because ψ varies its value with every change of the variable grinding condition. A grinding force also is unsuitable. In this paper, a new suitable evaluating function q is proposed, which is related to the strength of grain depending on the cutting time duration, or to the theoretical wear rate of grain. And, the cutting condition term contained in q is named Γ, and can be used instead of q.View full abstractDownload PDF (1086K) -
Hiroyuki MAKINO, Tadayoshi KOIZUMI, Yoshimi ITO1980 Volume 46 Issue 12 Pages 1493-1498
Published: December 05, 1980
Released on J-STAGE: June 30, 2009
JOURNAL FREE ACCESSThe experimental investigation has been made to clarify the relationship between the static hysteresisloop and the vibration damping capacity of a taper contact surface. From the experimental results, it was clarified that the value of the damping capacity λs=S/2E (S; area of hysteresisloop, E; stored energy) calculated from the static hysteresisloop increases proportionally with the 0.7 power of the amplitude, and that the logarithmic damping decrement measured from the damped free vibration curve of a shaft depends also on the vibration amplitude, increasing with the increase of the vibration amplitude. Besides, it was clarified that the logarithmic damping decrement changes with the vibration velocity and it increases with the increasing vibration velocity (natural frequency). From the results described above, it can be drawn that the damping capacity calculated by the static hysteresisloop shows the minimum value of the damping capacity of a contact surface. By the existence of the machine oil on a contact surface, the residual slip is larger than that of a dry contact surface, and the high damping capacity was observed, but there are no effects of the vibration velocity.View full abstractDownload PDF (1117K) -
Trial Manufactured Apparatus and Some Experiment of Super High Speed CuttingKozo KISHI, Hiroshi EDA, Hideo UENO1980 Volume 46 Issue 12 Pages 1499-1505
Published: December 05, 1980
Released on J-STAGE: June 30, 2009
JOURNAL FREE ACCESSThis paper deals with generation of the machined surface for the super high speed cutting of aluminium alloy and brass in orthogonal cutting in the high speed range, i. e. 100-1200 m/s. For example, extension of the cutting plastic zone can be decreased by increasing cutting speed V to a value greater than the propagation speed of plastic strain υεp of the materials to be cut. A cutting experiment, at speeds up to 1200 m/s, was carried out for reduction of the machined layer. The results are as follows: (1) An experimental apparatus, which enables stable cutting up to 1200 m/s, was developed. (2) Comparing cutting at 1 m/s with that at 1200 m/s, residual stress and hardness of the machined laver decreased by 90-95% and 85-90% respectively, and plastic flow was almost negligible. (3) Moreover, the distribution depth of both hardness and plastic flow decreased by more than 90%,View full abstractDownload PDF (1959K) -
Tetsuo OKAZAKI, Masato KOBAYASHI1980 Volume 46 Issue 12 Pages 1506-1511
Published: December 05, 1980
Released on J-STAGE: June 30, 2009
JOURNAL FREE ACCESSIn determining design conditions for an impact printer, it is necessary to study the ink transfer mechanism in impact printing and to clarify the relationship of print quality parameters, such as printed character stroke width and print density, to design conditions for printing mechanisms. This paper describes an analytical and experimental study of the liquid ink transfer mechanism using an inked ribbon in impact printing. The results obtained are as follows: (I) The liquid ink transfer mechanism can be well explained by the viscous flow model which assumes the structure of paper to be an arrangement of cylindrical capillaries and the ink to be a Newtonian fluid. (2) The quantity of ink transferred is proportional to the square root of the peak printing pressure and contact time, proportional to the mean capillary radius of paper, and inversely proportional to the square root of ink viscosity.View full abstractDownload PDF (3753K) -
Hiroshi KAMADA, Toshiharu IEKI1980 Volume 46 Issue 12 Pages 1512-1517
Published: December 05, 1980
Released on J-STAGE: June 30, 2009
JOURNAL FREE ACCESSThis report describes an optimum condition and a design application procedure for the automatic paper loading in the high speed line printer. The paper loading mechanism from friction rollers to tractor pins is discussed, and it is found that the optimum is given on condition that tensile force area is the most wide. As a result, design procedure is settled to not cut and try method. Also, it is indicated that dynamic phenomena such as paper deform and jumping are found, and the calculated results are in good agreement with experiments. The main conclusions are as follows. (1) The optimum condition for the automatic paper loading can be shown as V={√1+(l2/p)-1}-1. Where V; velocity ratio, l2; total tractor path, p; tractor pin pitch. (2) The paper loading stability area in dynamic phenomena are influenced specially with roller tensile force and paper thickness. (3) The time for automatic paper loading in high speed line printer can be reduced by one fourth compared with manual case.View full abstractDownload PDF (1249K) -
Anodic Dissolution Behavior of Ni-Cr AlloysEiji MAKINO, Toshikazu SATO1980 Volume 46 Issue 12 Pages 1518-1524
Published: December 05, 1980
Released on J-STAGE: February 16, 2010
JOURNAL FREE ACCESSThe effect of Cr content on high rate anodic dissolution behavior of nickel-based superalloys has been studied. The polarization curves and the dissolution current efficiency were measured with the specimens of Ni-Cr alloys from 0% to 60% Cr in 2M NaCl and 3M NaNO3 solutions at 30°C. The polarization measurements were carried out in static and flowing electrolytes, and the dissolution current efficiency measurements were carried out in flowing electrolyte under controlled current densities ranging from 1 to 100 A/cm2. The alloy containing 10% Cr dissolves in the active state at 100% current efficiency in NaCl solution. In NaNO3 solution, secondary passivation and oxygen gas evolution take place at the potentials above 1.4 V (vs. SCE), then the dissolution current efficiency is only 5-20%. The alloys containing≥30% Cr in NaCl solution and the alloys containing≥20% Cr in NaNO3 solution dissolve in the transpassive state at the potentials above 0.8 V (vs. SCE) and the dissolution current efficiency is about 100%, independent of current density.View full abstractDownload PDF (1716K) -
Characteristics of the SystemNobuyuki FURUYA, Hiroshi MAKINO1980 Volume 46 Issue 12 Pages 1525-1531
Published: December 05, 1980
Released on J-STAGE: June 30, 2009
JOURNAL FREE ACCESSA new type assembly robot called "SCARA" (selective compliance assembly robot arm) has been developed. The robot has two jointed link arms swinging about the parallel vertical axes and a tool at the end of the second link. The robot has a characteristic construction of "selective compliance", that is, the compliances in z direction and for x and y moment are small, while which in x and y direction and for z moment are large. Owing to the construction, the tool moves laterally without bending in an insertion process, and thus the peg fits quickly into the hole, correcting passively the error of position. In this report the characteristics of the system is discussed, and the actual results with prototype robot are shown.View full abstractDownload PDF (1396K) -
Error Compensation for the Ambient Temperature ChangeYoshimi TAKEUCHI, Toshio SATA, Makoto SATO, Hiroichi SUZUKI1980 Volume 46 Issue 12 Pages 1532-1536
Published: December 05, 1980
Released on J-STAGE: June 30, 2009
JOURNAL FREE ACCESSThe study presents the improvement of the working accuracy by removing the error for an ambient temperature change, which affects the working accuracy largely. A machining center is newly developed, where various kinds of remedies are considered against the thermal deformation from the design stage. Further, in order to maintain the accuracy of the machine under more severe environment, a program is made to estimate the error due to the ambient temperature change and to modify numerical control commands. The error is decided from the temperature distribution on the machine and is replaced to the displacement of the spindle. The possibility of the error compensation for the ambient temperature change is confirmed by boring- and endmilling experiments, together with the geometrical error compensation.View full abstractDownload PDF (1356K) -
Yuzo MORI, Naoya IKAWA, Toru OKUDA, Kazuhisa SUGIYAMA1980 Volume 46 Issue 12 Pages 1537-1544
Published: December 05, 1980
Released on J-STAGE: June 30, 2009
JOURNAL FREE ACCESSThe present research aims to realize the numerically controlled ultra-precision machining which can easily finish the work into an arbitrary shape by a single apparatus, utilizing the elastic fracture of the order of atomic size. Ultra fine powder particles are employed as the tool. Powder particles and water are mixed, and by utilizing the state of fluid lubrication of the mixed fluid, only powder particles are accelerated and made to collide with the material surface, so that the elastic fracture of the order of atomic size is achieved. This machining method is realized by shifting the elastic fracture region, controlling the feed speed numerically. A theory of the numerically controlled machining is theoretically introduced and experimentally proved. The machining apparatus and the machining system for this purpose are developed and the following results are obtained: (1) It is possible to remove the material with the accuracy better than ±0.01 μm by controlling the feed. speed or the dwelling time. (2) It is proved theoretically and experimentally that the numerically controlled Elastic Emission Machining is possible. The single necessary condition to achieve this machining is that the pre-worked surface is measurable. (3) The working technique is developed to satisfy simultaneously three requirements, that is, high-accuracy working, automatic working, and crystallographically and physically perfect mirror surface finishing.View full abstractDownload PDF (1615K) -
Deformation and the Affecting Factors in One Tooth of the BeltTakeshi SHIRATORI1980 Volume 46 Issue 12 Pages 1545-1549
Published: December 05, 1980
Released on J-STAGE: June 30, 2009
JOURNAL FREE ACCESSThe deformation and the affecting factors in meshing toothed belt with one tooth are discussed. In the theoretical analysis using the two dimensional finite element method, some nonlinear factors are considered. They are the nonlinearity of the elastomeric material, of the friction and the blankspace between the belt and the pulley. The analytical results show that the maximum stress is presented near the root of the tooth or near the point at which the belt parts from the pulley and that the displacement in each side is quasi-linear to the tensile force in case that the tension ratio is constant. This quasi-linearity results from the mixture of the each nonlinearity above mentioned. In the experiment of the enlarged two dimensional model belt and the XL-type belt with one tooth, the displacement in each side is measured when the each tensile force is added. The agreement between theory and experiment is satisfactory. Then the adequacy of the two dimensional analysis is confirmed, and it becomes clear that the deformation of the toothed belt is expressed by the material constants and the condition in contact with the pulley.View full abstractDownload PDF (1020K) -
The Difference of Working Mechanism due to the Size of Abrasive GrainMasato YOSHIOKA1980 Volume 46 Issue 12 Pages 1550-1555
Published: December 05, 1980
Released on J-STAGE: June 30, 2009
JOURNAL FREE ACCESSMgO single crystal is lapped and polished. The function of abrasive grains in lapping process is discussed on the basis of aspects of worked surface. Surface roughness and the depth of dislocation concentrated zone are measured. Obtained results indicate that machining mechanism varies as the size of abrasive grains used. When coarce grains are used, principal machining process is microfracturing produced by the pressing of each grain. On the other hand, when fine grains are used, it is micro-cutting by grain tips. Measurement of the depth of dislocation concentrated zone clarifies average weights on each grain. There is much diffrence in average weights between the case when coarce and fine grains are used. It is assured that this is the cause of the difference between machining mechanisms mentioned above. Furthermore, obtained values of average weight indicate that grains with especially large size may be crushed in earlier period of lapping.View full abstractDownload PDF (1738K) -
[in Japanese]1980 Volume 46 Issue 12 Pages 1556-1563
Published: December 05, 1980
Released on J-STAGE: June 30, 2009
JOURNAL FREE ACCESSDownload PDF (1783K) -
[in Japanese]1980 Volume 46 Issue 12 Pages 1564-1565
Published: December 05, 1980
Released on J-STAGE: June 30, 2009
JOURNAL FREE ACCESSDownload PDF (568K)
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